Improvement in felt-stretchers for paper-machines



.2vS`heets--Sheet I.

0. W. CLARK.. l 'Felt-St'retohers fdr Paper-Machines.

Patented Nov. 19,1878.-

lNvENToR l v .PETERS. FHOTO-LFI'HDGRAPHER. WASHINGTON. D( CY Y l2.Shet.s-Sh'eet;l 2. CLARK.' for Paper-Machines.

s T. e h c t e .P.. Llu S. Mw nu F Il 2 o. N

UNITED STATES. PATENT Gitaren.'-

oRsoN w. CLARK, or APIJLnroN, WISCONSIN.

IMPROVEMENT IN FELT-STRETCHERS FOR PAPER-MAQHINES.

Specification forming part of Letters Patent No. 210,097, dated November19, 1878; application iiled August 10, 1878.

To all whom 'it may concern:

Be it known that I, ORSON WILLLAMS CLARK, of Appleton, in the county ofOutagamie and State of Wisconsin, have invented certain new and usefulImprovements inPaper- Making Machines; Land Ifdo hereby declare thefollowing to be a full7 clear, and exact description of the invention,such as will enable others Skilled in the art to which it pertains tomake and use it, reference being had to the accompanying drawings, whichform part of this specification.

. My invention relates more particularly to that class of devices inpaper -making machines designed tol transversely spread or widen thefelt that takes up the pulp which forms the sheet of paper.

The well-known difficulty experienced by manufacturers of paper which iscaused by the contracting or shrinkage in width of the felt hasheretofore been soughttobe obviated in different ways. One form ofdevice` quite early used was to provide a vertically-arched rod, curvedalso in a horizontal plane, with its central body projecting forwardlyin the gen'- eral line of Adirection of the moving felt apron, said rodbeing provided with .rollers loosely axled thereon in longitudinal line,and partakin g of the general form of said rod. The endless felt apron,which conveyed the paper from the wire-cloth apron to the usual press'-ure and heating cylinderspasses over this rod, and as the-latter wasadapted to press vertically upward I against the -under side of thefelt, the tendency was to causel the material in said felt to be drawnoutward toward the respective side edges of the same; but a materialobjection to this device was found in the fact that the said upwardpressure against the felt weakened it and tended to make it more liableto wear, while it maintained it constantly subjected to strain, andcaused its line of direction to be vertically changed.

The form of device nowV generally in use is what is known as theelbow-roll, and consists of two distinct rolls of equal length,arrangedtransversely to the felt and in horizontal angular inclinationto its width. The outer extremities of the two rolls' are in rear oftheir respectivel inner extremities, which latter project forwardly andcentrally in the direction of the moving felt, so as to place each ofthe rolls inclined about fifteen degrees. to a straight line passingacross the felt par allel with its width. These rolls are jour# naled ina suitable frame beneath the felt,1and are adapted to press verticallyupward against the under side of the' same.' The 'degree of resultproduced in widening the feltdepends exclusivelyy upon the degree ofythisjupward pressure, and varies correspondin gly'withthe SameLThiselbow-roll, however, is very'da|naging in its effect upon the felt, andis in reality only used as a last resort, when the felt must either bedisearded'fromy use entirely or w'idened. The reason of this objectionis that produces` an angle, over which the center of the felt passes,and soon developsv a sagin the same,'whichY causes the felt to bewornout in a short time. y l My invention is designed to, provide aspreading device which will be free from 'the objectionable featuresattending the use of the several forms employed previously to the same;and consists, first, in` two pairs of rolls, one or both rolls of eachpair being journaled in yielding bearings, which are provided with meansfor regulating the tension on the rolls, said rolls having their axiallengths inclined about ten degrees (more or less) to the line of width'of the felt, and adapted to cause the latter to pass between said rollssubjected to their pressure action. Y This prevents any strain frombeing borne by the felt,A such as would be caused if there were but asingle roll pressing up against the felt. According to lmy device, acombined upper and lower pressure in vertical line is' brought -to bearupon the felt, and since the two pressures are equal in degree there isno resulting injurious effect to the felt, as the one pressurecounterbalances the other, and the felt is simply compressed between thetwo. f

Theinvention consists, secondly, in two pairs of rolls, one or bothrolls of each pair bein gj ournaled in yielding bearings, which areprovided with means for regulating the tension onthe rolls, the latterlocated angularly to the width of the felt, and adapted to receive thelatter in compression between them in a plane corresponding to itsgeneral movement, and without vertically changing the same or making araised angular formation therein. By thus causing the felt to enterbetween the rolls and pass out therefrom in one and the same plane inwhich it is located, respectively, in front and rear of said rolls, novertical tension is imposed upon it, and it is thereby enabled to lastthe longer in good serviceable condition.

The invention consists, thirdly, in two pairs of rolls, one or-bothrolls of each pairbeingjournaled in yielding bearin gs, which areprovided with means for regulating the tension ou the rolls, thelatterlocated augularly to the width of the felt, which passes throughbetween the same, said rolls having adjustable elastic com pressionrelative to each other. The advantage of this adjustment of the rollsunder spring pressure to and from each other is that thereby any degreeof yielding compression may be put upon the felt as may be required, tosuitably spread out the felt when the latter is in different conditionsor degrees of shrinkage.

.The invention consists, fourthly, in the combination of two pairs ofshort angle-rolls, one or both rolls of each pair being journaled inyielding bearings, which are provided with means for regulating thetension on the rolls, the latter adapted by their location to cause theside portions of the felt to pass between the upper and lower rolls,respectively, of the same, said pairs of rolls being inclined at anydesired angle to the width of the felt, with their inner extremitiesprojecting forwardly toward the line of direction of said movingfelt.This construction causes the material of the felt to be drawn from thelongitudinal central body of the same, and, together with the sideportions, to be distended transversely, so asto widen the felt from itscenter out on both sides thereof simultaneously and equally.

The invention further consists in such detail mechanical forms as Iprefer to employ in carrying out the main principles of my invention, asabove set forth.

Referring to the drawings, Figure l is a view, in perspective, of a partof a papermalr in g machine provided with my invention, and whichsufficiently illustrates the use of the same. Fig. 2 is a view, invertical sectional elevation, in a plane passing through x y of Fig. 1.Fig. 3 is a longitudinal vertical sectional view in a plane passingthrough one of the pairs of angle-rolls. Fig. 4 is a perspective view ofsaid angle-rolls mounted in a suitable frame, and shown detached fromany machine.

The invention is applicable to any papermaking machine, and the form ofthe latter herein shown is simply given as an example of its use.

Two pairs of rolls, A, are journaled in suitable manner, so that theymay be horizontally inclined in any desired angular degreerelative tothe line of width of the felt B, upon which they are to act.

The inner extremities of each pair of rolls respectively projectforwardly in inclination (more or less) from a straight line passingsquarely across the width of the felt,'thongh the same may be changed toany other suitable degree of inclination. Preferably they are also madeot' length proportioned to the width of the felt, substantially asrepresented in the drawings, as the same form a very practicable formot' device but, instead thereof, said rolls might be made shorter, orthey could be extended forwardly toward the longitudinal central body ofthe felt. They are located so as to cause the felt to pass in betweenthe upper and lower rolls of the respective pairs, and also to pass outtherefrom in one and the same plane in which it `is placed,both beforereaching said rolls and also after -leavin g the same. Thus the generallongitudinal line ot' direction of the felt is not changed by passagethrough these an gle-rolls, though the material of the same istransversely drawn out andthe felt widened. Hence, it the felt were`moving in a horizontal plane, as is usually the case, then there wouldbe no vertical change or al# teration of the same by reason of itssubjection to the action of my rol1s. Instead, however, of placing saidrolls in such location relative to the remaining parts of thepaper-machine as is here represented in the drawlngs, -I may locate themin any desired place.

The upper andlower rolls of each respective pair are adapted to be adjusted relative to each other, and to be maintained in juxtapositionunder elastic compression, so that they may be capable of` acting upondii'erent felts, or upon the saine felt in different conditions of useand shrinkage'correspondinglywith the degree of pressure necessary tospread the same. I preferably mount them in a suitable frame, consistingof annpper and lower sec; tion, to which, respectively, the'corresponding rolls of the two pairs are journaled. Said upper section,C, is vertically adjustable in sliding movement upon guidefrods D, andprovides bearing for the semielliptical springs E, which are likewiseadjustable upon the upper extremities ofthe bolt-shaftsF. Suitablefastening devices, such asare represented by the hand' clamping-nuts f,adjust the'tension of said springs, and cause the upper framesection tobearits rolls downward with a greater or less pressure upon the lowerrolls of each pair, which are journaled in the stationary frame-section.

It is evident that many changes 'of construction could bemade asregardsthe frame-work. Thus rubber or other resilient agent could besubstituted for the metallicl springs, and gen- Aerally the detailapparatus lcan be altered as desired.

It is also apparentI that the peculiar device for spreading the felt isapplicable to other and analogous purposes outside of paper-makingmachines; and hence the invention is not restricted in use to thelatter, but includes all result in addition to that-'ordinarily eiiectedby yielding tension-rollers, which is as follows Should the bearingsofthe yielding roller of each pair wear unevenly', or from other causethe tension on the roll of one pairexceed that of the roll of theopposite pair, the felt would be fed unevenly, and would run oft' theside of the rolls. This difficulty` is obviated by providing independentmeans for adjustingthe tension on the rolls 5 and by regulating thetension on the rolls of each pair the felt may be guided with thegreatest accuracy.

Having fully described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. In a felt spreading or widenin g device for paper-making machines,two pairs of rolls arranged in an inclination to the width of the felt,one roll of each pair being journaled in yielding bearings, and meansfor regulating the tension on the adjustable bearing-frames,substantially as set forth.

2. In a felt-spreading device for paper-making machines, aroll-supportin g frame consisting in the combination of an upper andlower horizontal section, said upper section being adjustable underelastic spring-pressure relative toV the lower section, and both saidsections having lon gitudinally-inclined rolls journaled therein,substantiallyvas set forth.

' 3. The combination, with the two framesections in which the upper andlower anglerolls are vrespectively journaled, of vertical guidelrodsconnecting the same, and boltshafts provided'with spring mechanism andclamping devices, adapted to adjust said sections relative to eachother, substantially as set forth.

In testimony that I claim the foregoing I have hereunto set my hand this5th day of August, 1878.

p ORSON WILLIAMS CLARK.

